add shell options to example config

etc/lfrc.example

@@ -1,6 +1,15 @@
 # interpreter for shell commands (needs to be POSIX compatible)
 set shell sh
 
+# set '-eu' options for shell commands
+# These options are used to have safer shell commands. Option '-e' is used to
+# exit on error and '-u' option is used to give error for unset variables.
+# Option '-f' disables pathname expansion which can be useful when $f, $fs, and
+# $fx variables contain names with '*' or '?' characters. However, this option
+# is used selectively within individual commands as it can be limiting at
+# times.
+set shellopts '-eu'
+
 # set internal field separator (IFS) to "\n" for shell commands
 # This is useful to automatically split file names in $fs and $fx properly
 # since default file separator used in these variables (i.e. 'filesep' option)
@@ -45,10 +54,11 @@ map r push :rename<space>
 
 # move current file or selected files to trash folder
 # (also see 'man mv' for backup/overwrite options)
-cmd trash %mv $fx ~/.trash
+cmd trash %set -f; mv $fx ~/.trash
 
 # remove current file or selected files (prompting)
 cmd remove ${{
+    set -f
     printf "$fx\n"
     printf "remove?[y/n]"
     read ans
@@ -57,7 +67,8 @@ cmd remove ${{
 
 # extract the current file with the right command
 # (xkcd link: https://xkcd.com/1168/)
-cmd extract %{{
+cmd extract ${{
+    set -f
     case $f in
         *.tar.bz|*.tar.bz2|*.tbz|*.tbz2) tar xjvf $f;;
         *.tar.gz|*.tgz) tar xzvf $f;;
@@ -69,9 +80,19 @@ cmd extract %{{
 }}
 
 # compress current file or selected files with tar and gunzip
-cmd compress %{{
+cmd tar ${{
+    set -f
     mkdir $1
     cp -r $fx $1
     tar czf $1.tar.gz $1
     rm -rf $1
 }}
+
+# compress current file or selected files with zip
+cmd zip ${{
+    set -f
+    mkdir $1
+    cp -r $fx $1
+    zip -r $1.zip $1
+    rm -rf $1
+}}